Method for fabricating high purity gold foil

ABSTRACT

The present invention provides a method for forming high purity gold foil. The method primarily includes the steps described as follows. Gold bullion is positioned in a vacuum environment and then vaporized using electrical process and thus becomes powder. Next, the gold powder suspended above the gold bullion is attracted and temporarily accumulated on the surface of the substrate due to the static electricity applied on the substrate. The particles of the gold powder gather and become the high purity gold foil.

BACKGROUND OF THE INVENTION

[0001] 1. Field of the Invention

[0002] The present invention relates to a method for fabricating high purity gold foil.

[0003] 2. Description of the Prior Art

[0004] Gold is excellent in ductility and is expensive. Therefore, gold is generally formed using plating or coating on the surface of other metal so as to reduce the ratio or the amount of gold. However, in the conventional fabricating method, the resulting purity of gold is not pure. Besides, in the fabricating process, many impurities are added and which reduces the value of gold.

[0005] Besides, some people believe that eating the fragment of pure gold foil will benefit health. However, the eaten fragment may have not high purity gold foil and includes many contaminants. Therefore, consideration of eating such the gold foil should be given.

[0006] For example, the present-day gold foil is claimed to be 99% purity. Actually, the so-called high purity indicates the purity of the gold before adding silver or copper. In prior art, adding silver or copper to gold is necessary during forming a sheet of gild foil form gold. As a result, the resulting gold foil has not the desired purity. Presently, the eaten gold foil is formed by such the method. Furthermore, in the extra treating process, other impurity may be incorporated in the gold foil and which leads to poor purity. Since the conventional gold foil may includes some impurity and silver or copper, it is unclean to eat the conventional gold foil. Alternatively, the healthful effect of the gold foil is encumbered with the impurity.

[0007] The conventional method for forming gold foil is described as follows. At first, a gold bullion is heatedly melted, clamped by two separating papers and then is pressed to form a sheet of gold. The sheet of gold is cut away to form the substrate having the desired size. The substrate clamped by the separating papers is repeatedly beaten to extend the, substrate until a gold foil is formed. During the manufacturing process, the additive including silver or copper may be used to form filmy gold foil. However, such the method incorporates many impurities and leads to lowered purity.

[0008] The gold contained in a container is heatedly melted and changed from solid to liquid. Inevitability, the liquid gold touches the impurity of the container surface. This is the first contaminant. The temperature required for melting the gold is high. Under this condition, the liquid gold may chemically or physically react with the container. This is the second contaminant. Therefore, the resulting gold foil is unclean.

[0009] During the pressing step, the apparatus or the separating papers directly contact the gold and supplies force on the gold. As a result, many impurities are incorporated in the gold. This is the third contaminant.

[0010] In order to enhance the ductility of the gold, prior art adds other metal, such as silver or copper, into the gold. However, the additional metal leads to impure gold. It is well-known copper is harmful to human body. This is the fourth contaminant.

SUMMARY OF THE INVENTION

[0011] Therefore, the main object of the present invention is to provide a method for fabricating high purity gold foil.

[0012] The present gold foil is consisting of the fine gold particles temporarily combined. Therefore, it is easy for water to dissolve the, present gold foil. Besides, it is easy for human body to absorb the fine gold particle.

DESCRIPTION OF THE PREFERRED EMBODIMENT

[0013] Embodiment

[0014] The present invention provides a method for forming high purity gold foil. The method primarily includes the steps described as follows. Gold bullion is positioned in a vacuum environment and then vaporized using electrical process and thus becomes powder. Next, the gold powder suspended above the gold bullion is attracted and temporarily accumulated on the surface of the substrate due to the static electricity applied on the substrate. The particles of the gold powder gather and become the high purity gold foil.

[0015] After the static electricity applied on the substrate is removed, the gold foil peels off the substrate.

[0016] According to the above-mentioned method, there is few impurity contained in the gold foil. Besides, the high purity gold foil is still available even though silver, copper or other material is not added. The measured purity of the gold foil based on the present invention at least achieves 99.9%. The gold foil is easy to be absorbed by the human body since the gold foil consists of fine powder. The particle of the gold powder is fine and has an invisible diameter of 0.03μm.

[0017] The gold foil provided by the present invention has a purity of at least 99.9%. That is, the present invention can improve the conventional disadvantage—lower purity.

[0018] Besides, the gold foil provided by the present invention is formed of gold powder temporarily gathers and has a high purity and. Therefore, the present gold foil is easy to be decomposed by shake, or dissolved by water and thus returns to gold powder. That is, the gold foil is easy to be absorbed by the human body and clean.

[0019] Comparison with prior art

[0020] 1. The present invention has a high purity that prior art cannot provide.

[0021] 2. Prior art contains many contaminants. However, the present invention contains few contaminant.

[0022] 3. Prior art has to add silver or copper to form thin gold foil. The present invention does not need to add any silver or copper.

[0023] 4. The conventional gold foil is unclean because it contains many contaminants. The present invention is clean because it contains few contaminant.

[0024] 5. Even though prior art cuts the gold foil to piece, the fragment of the conventional gold foil is still hard to be absorbed by the human body.

[0025] On the contrary, since the present gold foil is composed of fine gold powder, the present invention is easy to be eaten and then absorbed by the human body.

[0026] In sum, the present invention provides a method for forming high purity gold foil without any additional silver or copper. Besides, the present gold foil is composed of fine gold powder easy to be absorbed by human body.

[0027] As is understood by a person skilled in the art, the foregoing preferred embodiments of the present invention are illustrated of the present invention rather than limiting of the present invention. It is intended to cover various modifications and similar arrangements included within the spirit and scope of the appended claims, the scope of which should be accorded the broadest interpretation so as to encompass all such modifications and similar structure. 

What is claimed is:
 1. A method for forming high purity gold foil, comprising the steps as follows: gold bullion positioned in a vacuum environment being vaporized using electrical process and thus becoming powder; using static electricity to make said gold powder suspended above the gold bullion be attracted and temporarily accumulated on a surface of a substrate, thereby temporarily gathering particles of the gold powder.
 2. The method according to claim 1, wherein said gold powder has a diameter of about 0.03 micrometer.
 3. The method according to claim 1 or 2, wherein said gold foil is easy to be dissolved in water. 